BigWopHH

Forgive me if this has been discussed before. I'm just wondering about the performance impact on a car when upgrading to lighter-weight wheels...

I know technically, since the wheels are lighter, they'll require less force to rotate, hence will rotate easier, which should theoretically help performance. But is the impact of shaving 4-5lbs off each wheel noticable when a car weights thousands of pounds?

YetiTL

Well, according to physics, shaving 1 lb of wheel and tire weight can represent the equivalent of shaving 6-10 lbs of chassis weight. So if my set of OZ lightweight 18'' wheels weight 7 lbs per wheel, it's like I just shaved 7 X (6 to 10) X 4 = 168 to 280 lbs of chassis weight reduction.

It should improve handling, braking, acceleration but also ride quality as the suspension doesn't have to work as hard to stabilize a 43-45 lbs wheel + tire rather than a 52-55 lbs wheel+tire

I'll try that for the spring/ summer/ fall and I'll make my own judgement. Since I was going to change rims & tires, I decided to go lightweight to experiment a little bit...

Here's a link for you, be sure to read part 2 also.

http://hondaswap.com/general-tech-ar...art-1-a-29057/

rondog

iTrader: (1)

You won't feel a 5 lb difference, heck, a difference of 20 degrees in outdoor temprature will make a bigger differenc eon the performance really. I've had Super lightweight wheels (18" forged Devotions weighing 16 lbs a piece) all the way to relatively heavy 20" wheels (20" DT3 weighing about 29 lbs) and I tell you the car really doesn't feel that much slower at all. Thats not to say that it isn't slower, but the feeling can be masked by an aggressive exhaust note and tire grip. For instance, the 255 pirelli tires barely ever chirp off the line or between shifts so the car feels slower, less powerful. but I know its faster because the grip is all there.

Also, too light a wheel and the tires will have a hard time hooking up off the line, thats the problem I had with the 16 lb wheels, they would just spin too much off the line. Bottom line, just get a good looking wheel and don't lose sleep over a few lbs difference, this isn't an indy car logging hot laps.

YetiTL

Thanks Ron! This is a great answer to put things in perspective!

Like I said in my thread, I wanted to know the difference between more standard wheels and lightweight ones. If it's not noticable, then I'll be back and buy some super nice Harrow. Hmmm...scratch that, I'll buy some super nice Harrow wheels anyway since I like this model very much!

Is it just me but we're all a bunch of OCD type of guys around here?? lol!

CleanCL

iTrader: (4)

From my experience, you will feel a difference if you lose 5 lbs per wheel. Thats A LOT. I mean it's one thing if you put cheap tires on light weight wheels, and great tires on heavier wheels. But put great tires with grip on lightweight wheels and I guarantee you will feel a difference.

YetiTL

Good to know! And it's more than 5 lbs, more like 7-8 lbs often per wheel.

Anyway, while I think there's nothing wrong with the base alloy wheels, it might be worth to go lightweight for the 4G since it's so heavy to begin with...

Time will tell, I can't wait til spring 2010

wasupdog

iTrader: (2)

lightweight wheels make a massive difference. 5lb's lighter per wheel is huge. it feels a lot similar to when you're driving a fat friend or two around and you notice that the acceleration is decreased.

the first thing you'll notice when you put on lightweight wheels is that when you drive how you normally drive, you'll be going faster than you normally are when you look down at the speedometer. acceleration, braking and steering are all enhanced with lighter rims, although the most noticeable difference off the bat is acceleration. there's a reason that all of the performance cars like evo's, sti's etc. run 18" or smaller 1-piece monoblock forged rims.

c_potvin

I definitely feel a difference in how the car accelerates between my 3G 6MT stock 17" wheels and my summer A-Spec 18" wheels setup. The car accelerates more freely with the 17's. I don't know if it's only the weight difference or the repartition of the weight (mass is more difficult to accel/decel if far from the center).

Carl

YetiTL

Yes, the farther the mass is from the point of rotation, the greater the effect on performances.

rondog

iTrader: (1)

I beg to differ, the mass position between rubber and metal is the same, the overall diameter of the wheel and tire combo is the same between the two sizes. Don't forget that 20 lbs rubber weighs just as much as 20 lbs of aluminum. Maybe this physics apply when you're calculating alot less horsepower down to the decimal under extremely controlled situations, but from my experience (and trust me, I change wheels every month) the difference from wheel to wheel is not felt, unless it's a drastic difference like 8 lbs or so. other aspects of driving, down to the asphalt condition will make a car feel faster or slower more so than just the wheels.

This is my honest interpretation, and my feedback on this matter is not that beneficial to me, especially since our wheels are much lighter than stock. I'm just sick of everybody pinching ounces and making a decision on wheels based on weight like they are competing for the formula 1 grand prix championship. These are daily drivers. If you are that concerned with saving weight to that degree, you should uninstall all the accessories, gut the interior and replace the body panels with carbon fiber to save weight.

I promise I will be running an experiment were I clock a 0-60 run with two different weight wheels to show the difference, it will barely be noticeable if at all.

YetiTL

I understand what you're saying and I think it's true that in reality, the weightloss from wheels might not be appreciated during normal driving, after all, we go mainly from 0-35mph with traffic lights, pedestrians & other stuff going around.

What can't be argued is the law of physics behind the rationale (the moment of inertia, unsprung weight and all that). Now, while lighter wheels can make a difference, the real question is twofold: 1) how much lighter are they compared to stock ? and 2) am I in a situation where I can exploit the increased performance (if any)?

I, myself, will experiment during spring, early summer to test if there is really a difference. My summer wheels weight 44,5 lbs each compared to 52-53 lbs stock so it's a 7,5-8,5lbs weightloss. While the law of physics tell me I should feel a difference, the reality of driving in a densely populated area might temper any performance gain.

The way I analyzed this was to look for wheels I like (I like classic 5 spokes designs) then find the lighter ones to try it. Since this car is my first that I mod, I have many experiments to do before I come to conclusion on a myriad of topics.

But the point Rondog make is very valid, the 4G TL is a DD for most of us, not a track car by any means so let's not get crazy about the wheels weight too much. Just enough to stir good exchange!

Now, I meant no disrespect Rondog as you're far more knowledgeable about wheels than I'll ever be and if your wheels are mugh lighter than stock, then it's all good. I happen to be a fan of your Harrows wheels so if my OZ Crono HT do not satisfy me, I'll be glad to buy yours!

I also have an honest question: why don't you put your wheels weight on your great website, some manufacturers do this and I liked it, it helps when comparing stuff.

Have a great day!
-YetiTL

rondog

iTrader: (1)

This wasn't directed towards anybody in particular, I was just ranting.

As far as the wheel weights on the website, it's not somethign I want to brag about, only because there are wheels lighter than ours. But our selling point is really about quality and style rather than performance and racing. So even tho I consider weight as a a factor when engineering, I give the strength of the wheel and load rating a priority when engineering the prototype.

YetiTL

No worries, I have a thick skin and I didn't want to cause any grief or such. I understood you were ranting. Ok course, reading some posts by wannabees about how a 0,5lb difference made their cars 0,012234592 sec quicker can become tiresome quite fast!

Btw, your wheel weights seems very good! That was what I was talking about: I love your work and knowing you make lightweight yet superb wheels will definitely keeps me interested in buying your wheels in the near future.

Have a great day!
-YetiTL

SatinSilverAV6

iTrader: (2)

From the experience that I have had, the wheel weight makes a big difference. I have gone from my stock 205-60-16's to 235-40-18's to 215-50-17's. My stock setup weighed 43lbs. The 17's w/tire weigh 47lbs and my 18's w/tire weighed 55lbs. The difference between the 16's and 17's were minimal but the 18's just made this car more lethargic off the line and slower throughout the whole RPM band. Many races with friends and daily driving determined the difference for me. So I sold the 18's.